Mechanical impact printers are known to the prior art including a print station comprising a continuously rotating print wheel having a plurality of successive raised elements located on a circumferential surface thereof and an adjacent hammer mechanism which is selectively controllable to impact, by means of a hammer surface, an interposed elongated strip of print stock and an ink ribbon against one of the raised elements on the circumferential surface of the print wheel, thereby imprinting a character on the print stock. The hammer mechanisms of the prior art have included a hammer assembly comprising an elongated hammer having the hammer surface at one end thereof and an actuating surface at another end thereof which is engaged by a hammer actuating means which is capable of substantially reciprocative, planar movement. The elongated hammer itself is supported for planar, reciprocative movement above a similarly elongated support member by a pair of linear leaf springs extending between the support member and the elongated hammer in a spaced-apart, parallel manner.
In order to insure that the hammer surface is vertically aligned with the raised elements on the circumferential surface of the print wheel when the hammer surface impacts thereon, the prior art has taught means coupled to the support member of the hammer assembly for adjusting the orientation of the support member, and therefore the hammer, with respect to a fixed support.
The prior art apparatus has been disadvantageous, however, in requiring a complicated mechanism sufficient to allow both horizontal and vertical adjustment of the support member, and therefore the elongated hammer, as well as allowing adjustment of the vertical inclination of the hammer surface. In addition, the prior art apparatus has been difficult to utilize in that adjustments in vertical position of the hammer assembly adversely affect pre-set adjustments in the horizontal position thereof, with a resultant increase in the amount of time needed by a technician to properly setup and align the hammer assembly. Further, the prior art apparatus has required many expensive and complicated machined parts for its implementation.
It is therefore an object of this invention to provide an improved hammer assembly which overcomes the disadvantages of the prior art.
It is a further object of this invention to provide an improved hammer assembly for impact printers which, when installed in a hammer mechanism of an impact printer, permits easy and fast adjustment of horizontal and vertical location of the hammer assembly in a predetermined plane of hammer movement while yet allowing similarly easy and fast adjustment of the vertical inclination of the hammer surface.
It is another object of this invention to provide such an improved hammer assembly which is simple of construction and inexpensive of manufacture.
It is still another object of this invention to provide an improved adjusting mechanism for utilization for such an improved hammer assembly which requires a minimum of moving parts.